![]() |
Register or Log In To remove these advertisements. |
|
|
![]() |
|
Thread Tools | Display Modes |
|
![]() |
#1 |
Registered User
Join Date: Sep 2014
Location: Richfield, Oh
Posts: 112
|
![]()
... and what is your engine/tranny/rear end ratio?
![]() I know most people don't care about fuel mileage but I noticed my 68 C10 was sucking gas like crazy so I started checking and am only getting 10.5 mpg. I'm just puttering around town and to a few car shows now and then, nothing fast or aggressive. So my setup is a 350 with pretty much stock cam and crappy 8.5:1 compression, an Edelbrock (quadrajet type) carb and headers. The tranny is a Turbo 400/stock torque converter and the rear end is a 12 bolt 3:08 limited slip. I was thinking this truck sould normally get around 14 or 15 mpg. Maybe it's because the tires are larger and the body is not aerodynamic? Ok so waddaya got and what's your mileage looking like? |
![]() |
![]() |
![]() |
#2 |
Senior Member
![]() Join Date: May 2012
Location: phoenix az
Posts: 442
|
Re: What kind of gas mileage do you get with your 67-72?
I have just about the same running gear, but with a 350 tranny. I think the most I've gotten is 12 mpg. Maybe someone else gets better mpg
mike
__________________
my build thread http://67-72chevytrucks.com/vboard/s...d.php?t=522167 vietnam vet 67-68 |
![]() |
![]() |
![]() |
#3 |
Senior Member
![]() Join Date: Dec 1999
Location: Spring Valley, Ca.
Posts: 1,112
|
Re: What kind of gas mileage do you get with your 67-72?
I'm getting about the same as you. 60 over 350 edelbrock 4bbl. 700r4 3:56 posi.
__________________
Smitty '71 Short Fleetside Spring Valley, Ca. |
![]() |
![]() |
![]() |
#4 |
Registered User
Join Date: Aug 2014
Location: Mena,Arkansas
Posts: 485
|
Re: What kind of gas mileage do you get with your 67-72?
12 to 14 MPG is not out of reach.Keep your tire pressure at the top of the safe usable range for your tires and keep it in good tune and you should do better. I do know that fuel with ethanol tends to drop mileage a bit. Mine is a C-20 with a 327, TH 350 and 3.73 gears. I get about 14 to 15 MPG.
__________________
68' with no bells or whistles unless I add'em. |
![]() |
![]() |
![]() |
#5 |
Registered User
Join Date: Apr 2017
Location: Spokane, WA
Posts: 101
|
Re: What kind of gas mileage do you get with your 67-72?
6-7mpgs
![]()
__________________
71 Cheyenne LWB - RideTech Air, zz502, 20" Torq Thrusts 16 Sierra - Bilstein 6112/5160, 33" Duratracs, Method Race Wheels, GMPP Intake, Borla Exhaust 15 4Runner - Icon Coilovers, 33" Duratracs, Pro Comp Wheels, NFABs 16 Malibu Response TXi |
![]() |
![]() |
![]() |
#6 |
Registered User
Join Date: Jan 2009
Location: San Antonio, Texas
Posts: 1,374
|
Re: What kind of gas mileage do you get with your 67-72?
I have stock 350, stock quadrajet, stock TH350 transmission with .308 gears, and I get between high 12 to mid 13 mpg, depending on where and how I'm driving
__________________
1972 C10 LWB, 350/350 Deconstruction began 5/2009, mostly completed restoration, 5/2017 |
![]() |
![]() |
![]() |
#7 |
Who Changed This?
![]() Join Date: Jan 2013
Location: Simi Valley, CA
Posts: 10,373
|
Re: What kind of gas mileage do you get with your 67-72?
Like my sig says, 400/400THM/3.54 axle, factory equipment, except the engine and trans have been rebuilt. I haven't checked it without the travel trailer; when towing that, I get 7 MPG. I recall my FiL telling me it used to get 13 mpg, but we put a 12" taller camper shell on it, so it's going to have dropped because of that.
__________________
~Steven '70 Chevy 3/4T Longhorn CST 402/400/3.56 Custom Camper Simi Valley, CA |
![]() |
![]() |
![]() |
#8 |
Florida Edition
![]() ![]() Join Date: Oct 2010
Location: Fruitland Park, FL
Posts: 4,025
|
Re: What kind of gas mileage do you get with your 67-72?
I'm not much help because I really don't care, I just enjoy.
402 /400 /3.08 posi
__________________
70 GMC Short Stepside "Rose"-An American Beauty: Factory 402/TH400, AM/FM, AC, Tilt, Tach, Buckets, Posi, PS, PB, 3-5 Drop, Complete Resto-Rod 67 C-20 Slant Back Wrecker "Mad Max" 67 C-10 Ratrod "Step-N-Wolf" 71 Serro Scotty Sportsman camper "Scotty" 97 LT1 Z28 "The Hornet" Link to more pics of "Rose" http://67-72chevytrucks.com/vboard/a...p?albumid=1684 Check out my "Cheap Tricks" thread and add to it if you can, lots of good info there. http://67-72chevytrucks.com/vboard/s...d.php?t=489394 |
![]() |
![]() |
![]() |
#9 |
Registered User
![]() Join Date: Mar 2005
Location: Jurupa Valley, Ca
Posts: 1,210
|
Re: What kind of gas mileage do you get with your 67-72?
Around 14 mpg with a stock 350, 200r4 trans and 4.10 gears. This is mostly around town with a little freeway at 70 mixed in.
__________________
Terry 1970 Custom Camper/C20 , GM Crate 350/7004R, Dana 60, factory AC |
![]() |
![]() |
![]() |
#10 | |
Who Changed This?
![]() Join Date: Jan 2013
Location: Simi Valley, CA
Posts: 10,373
|
Re: What kind of gas mileage do you get with your 67-72?
Quote:
![]()
__________________
~Steven '70 Chevy 3/4T Longhorn CST 402/400/3.56 Custom Camper Simi Valley, CA |
|
![]() |
![]() |
![]() |
#11 |
Registered User
Join Date: Jun 2012
Location: Poway, CA
Posts: 119
|
Re: What kind of gas mileage do you get with your 67-72?
1968 GMC half ton fenderside. Stock 250 six, turbo 400 trans, 3.54 rear end. My daily driver for about 2 years. 13-15 mpg.
|
![]() |
![]() |
![]() |
#12 |
Registered User
Join Date: Sep 2018
Location: Newcastle, New South Wales, Australia
Posts: 139
|
Re: What kind of gas mileage do you get with your 67-72?
stock 350, 4 speed, 4.57 diff on 8.75r16.5 tyres, if I sit on or under 60, its 15mpg.
any faster and it drops to 12mpg. Bone stock in every way, 72k on clock, stock Qjet. |
![]() |
![]() |
![]() |
#13 |
Registered User
![]() Join Date: Dec 2012
Location: Vancouver, Washington
Posts: 1,644
|
Re: What kind of gas mileage do you get with your 67-72?
I get 12 ish with the non-ethanol premium I use.
__________________
1968 Chevrolet C/10 LWB - 327, TH350 - 4/5 Drop |
![]() |
![]() |
![]() |
#14 |
Registered User
Join Date: Jul 2018
Location: Catskill Mountains,NY
Posts: 8,461
|
Re: What kind of gas mileage do you get with your 67-72?
Really 10 mpg around town is about the norm for a truck made when gas was 45 cents a gallon. Mine gets 12 on the highway doing 60. And that's in 4200lb box.
__________________
Mark 72 c20 custom camper Husky edition, 66 SS396 Chevelle 1964 Hawk, 63 Avanti,62 lark 1969 AMX , 1968 c20 stepside ,85 K20 1977 Suburban sold 68 anniversary. |
![]() |
![]() |
![]() |
#15 |
Old member
Join Date: Jan 2002
Location: Liberty, & Garden City S.C. , U.S.
Posts: 19,936
|
![]()
71 with 2014 LS 6.0 and 4L80-e trans. 4:10 gears get 16-18 running 75-80 MPH with the AC on.
Ramp truck might get 12 with 350 and a granny 4 speed in it. No idea what rear end gears are. ![]()
__________________
1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver Seeing the USA in a 71 ![]() Upstate SC GM Truck Club 2013,14 and 2016 Hot Rod Pour Tour http://upstategmtrucks.com/ Get out and drive the truck this summer and have some fun! It sucks not being able to hear! LWB trucks rule, if you don't think so measure your SWB! After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs. |
![]() |
![]() |
![]() |
#16 |
Registered User
Join Date: Dec 2007
Location: Nanaimo B.C.
Posts: 604
|
Re: What kind of gas mileage do you get with your 67-72?
460 / 400 trans / 373 rearend I cant pass a gas station .
![]()
__________________
I was hooked on these trucks since 1982 when I drove my budys fathers 1968 Custum GMC 396 automatic dana 60 rear with a power lock diff what a ride more fun then we will we can ever tell!! |
![]() |
![]() |
![]() |
#17 |
Registered User
Join Date: Apr 2015
Location: East Tn (In the heart of the Smoky Mtns)
Posts: 1,868
|
Re: What kind of gas mileage do you get with your 67-72?
I’m satisfied if I average 13-15 on the highway. I will stop for gas at 200ish miles, but try not to go less than an 1/8th before stopping. If I put a load, or have long hills, and the ol girl drinks like a sailor on shore leave. Doesn’t matter though, she ain’t goin nowhere
![]() I run a standard 350/4bbl TH350, and 3.73 diff |
![]() |
![]() |
![]() |
#18 |
Registered User
Join Date: Jan 2017
Location: Larkspur, Colorado
Posts: 916
|
Re: What kind of gas mileage do you get with your 67-72?
SWB fleet 1/2 ton, '99 roller cam 350 9.8 compression w/ mild cam, Edelbrock performer intake and AFB carb, headers, TH400 w/2500 stall, 3.54 rear. 15mpg @ crystal 65mph, 11mpg @ 75mph, 10-12mpg mixed driving. 10mpg pulling the race car on a trailer @ 60 mph. 5000-7500 feet elevation.
In my years of engine building I found a typical V8 will get one additional mile per gallon per point of raised compression....... Steve weim55 Colorado Last edited by weim55; 10-01-2018 at 11:12 PM. |
![]() |
![]() |
![]() |
#19 |
Registered User
Join Date: Aug 2015
Location: Los angeles
Posts: 160
|
Re: What kind of gas mileage do you get with your 67-72?
WOW! This is great, i am doing the same set up with a 2004 6.0 lq9. Same rear end ,same transmission. I have a set of 16.5 inch slots That i hope to run with 33” tires with.Did you do a build thread by any chance?
|
![]() |
![]() |
![]() |
#20 | |
Old member
Join Date: Jan 2002
Location: Liberty, & Garden City S.C. , U.S.
Posts: 19,936
|
![]() Quote:
I have 20" wheels on it all around. ![]()
__________________
1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver Seeing the USA in a 71 ![]() Upstate SC GM Truck Club 2013,14 and 2016 Hot Rod Pour Tour http://upstategmtrucks.com/ Get out and drive the truck this summer and have some fun! It sucks not being able to hear! LWB trucks rule, if you don't think so measure your SWB! After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs. |
|
![]() |
![]() |
![]() |
#21 |
Senior Member
![]() ![]() Join Date: Oct 2015
Location: Brownsburg, IN
Posts: 1,092
|
Re: What kind of gas mileage do you get with your 67-72?
My K1500 gets 10.5 mpg. I was in high school during our trucks birth years, gas cost from 28-33 cents per gallon then. A 5 dollar bill almost bought a full tank back then.
__________________
1972 Blazer Highlander 1971 GMC K1500 SWB (sold) 2004 Corvette Z06 CE |
![]() |
![]() |
![]() |
#22 |
Registered User
Join Date: Jun 2014
Location: Tahuya WA
Posts: 560
|
Re: What kind of gas mileage do you get with your 67-72?
350/350 combo 3.07 rear end.
What kind of mileage do I get? I got a bug. ![]() ![]() |
![]() |
![]() |
![]() |
#23 |
Special Order
![]() ![]() Join Date: Nov 2004
Location: Mt Airy, MD
Posts: 85,859
|
Re: What kind of gas mileage do you get with your 67-72?
I don't want to talk about it!
It sucks now, but used to get a steady 12.5 no matter how I drove, hiway or country roads. It's been more like 10 in more recent years. I put different heads on a couple years ago and now it seems to be just under 10.... '72 K2500 350/TH350/4.10 with 285/75-16 Goodyear Duratracs
__________________
"BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed" GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project) GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling) Tim "Don't call me a redneck. I'm a rough cut country gentleman" R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~ |
![]() |
![]() |
![]() |
#24 | |
Registered User
Join Date: Sep 2011
Location: Ark City, Kansas
Posts: 3,332
|
Re: What kind of gas mileage do you get with your 67-72?
Quote:
Let me know if you ever want it worked on. Some parts and knowledge from Cliff might help it a lot!!! Jeff |
|
![]() |
![]() |
![]() |
#25 |
Registered User
Join Date: May 2013
Location: Colorado Rocky Mountains
Posts: 263
|
Re: What kind of gas mileage do you get with your 67-72?
LWB fleet 1/2 ton, 350 300 h.p. cam, Edelbrock performer RPM, 750 cfm AFB, ramhorns ,2.5 true dual exhaust, CH 465 4 spd, 3.73 axle ratio. 15.25 mpg @ 65-70 mph 5000' to 9000' elevation.
All the Best, Dirk |
![]() |
![]() |
![]() |
Bookmarks |
Thread Tools | |
Display Modes | |
|
|